YS = 2/3 × ( YV ) *.&.* SV = 1/3 × ( YV )
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YS = 2/3 × ( YV ) 
4x + 14 = 2/3 × ( YV ) 
Multiply both sides by 3/2 
( 4x + 14 ) × 3/2 = ( YV ) × 2/3 × 3/2 
YV = 6x + 21  ( ☆ ) 
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SV = 1/3 × ( YV ) 
1 + 3x = 1/3 × ( YV ) 
Multiply both sides by 3 
( 1 + 3x ) × 3 = ( YV ) × 1/3 × 3 
YV = 9x + 3  ( ♡ ) 
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YV = YV 
( ☆ ) = ( ♡ ) 
6x + 21 = 9x + 3 
Subtract both sides 3 
6x + 21 - 3 = 9x + 3 - 3 
6x + 18 = 9x 
Subtract both sides 6x 
6x - 6x + 18 = 9x - 6x 
18 = 3x 
Divide both sides by 3 
18 ÷ 3 = 3x ÷ 3 
x = 6 
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YV = 6x + 21 = 9x + 3 
YV = 6(6) + 21 = 9(6) + 3 
YV = 57